Area Forecast Discussion
Issued by NWS Topeka, KS
Issued by NWS Topeka, KS
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016 FXUS63 KTOP 031745 AFDTOP Area Forecast Discussion National Weather Service Topeka KS 1245 PM CDT Fri May 3 2024 .KEY MESSAGES... - Line of thunderstorms moves in from the west around/after midnight tonight, with potential for a few strong to severe storms. - Greater potential for severe weather Monday as a strong upper trough approaches. - Temperatures remain near to a bit above average. && .DISCUSSION... Issued at 426 AM CDT Fri May 3 2024 A brief break in rain chances this morning, as high pressure has moved in across the region. Light winds and clear skies, along with lingering moisture from our recent rain, have allowed for some patchy fog to develop in lower lying areas. This will linger until an hour or two after sunrise when deeper mixing occurs. The daytime hours will remain dry and mostly sunny, with temperatures warming into the 70s. Can`t completely rule out an evening storm north of I- 70 as CIN lowers with increasing moisture/heating, but the better storm chances arrive later overnight as a cold front approaches from the west. There is increasing confidence that a line of storms will initially be ongoing across northwestern Kansas, moving into north- central Kansas after midnight. Given around 1500 J/kg of MLCAPE and 30-40 kts of shear, a few strong to severe storms will be possible. The linear storm mode will keep damaging winds as the primary severe threat, with some isolated quarter size hail also possible. CIN increases with time and eastward extent, so expecting a gradual decrease in severe probabilities while the line moves across northeast and east-central Kansas. The front then moves east of the area by late morning Saturday. Just a few lingering shower chances by Saturday afternoon as cooler and drier air is advected southward. More rain chances arrive Sunday with a weak shortwave passing just to our south. Instability remains very limited so not expecting much if any severe weather. Severe weather chances significantly increase for Monday as a deep upper low becomes negatively tilted as it ejects eastward over the central Plains. Guidance is in good agreement in 65-68 degree dewpoints ahead of the dryline/cold front, supporting 2000-3000 J/kg of MLCAPE. One possible fly in the ointment would be if the strong upper forcing allows morning or early afternoon convection to develop and decrease instability for the afternoon. But otherwise, wind profiles strongly support supercells. These would initially develop off the dryline across central Kansas during the afternoon, moving northeast during the evening, and would be capable of large hail, damaging winds, and tornadoes. Several days to allow the details to come into place, but certainly a day to watch. Tuesday into Wednesday, the deep upper trough becomes centered over the Northern Plains, with several embedded shortwaves moving around its southern periphery. By this point, roughly 80% of ensemble guidance keeps the now quasi-stationary front southeast of the area. This would also keep severe weather chances southeast of our area, with temperatures staying near to slightly above average. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1238 PM CDT Fri May 3 2024 Cloud cover will increase this afternoon. A few models are showing MVFR conditions, while others are not. Have kept VFR conditions through the afternoon for now, but will amend if CIGS are lower than currently expected. TS will be the next concern as a line of storms is expected to impact airports late tonight/early Saturday morning. Timing may need to be tweaked slightly, but current thinking for impact timing is the 09-12Z timeframe as storms move from west to east across the area. Wind gusts to 30kts can`t be ruled out with storms, with isolated higher gusts. Lingering MVFR CIGS could occur through the morning hours before VFR returns late this period. && .TOP WATCHES/WARNINGS/ADVISORIES... None. && $$ DISCUSSION...Reese AVIATION...Teefey